378 Letters of cm African Traveller. 



the branch Fammeticiis to the bed fatal to Louis IX. ; and 

 finally returned to Grand Cairo. 



'Now that, thanks to the jnagnanimous Viceroy of Egypt, 

 the brave Mahomet Ali, and his faithful minister Burgoss 

 JusuiF, I am furnished with ample and generous means of pe- 

 netrating into spaces shut up by the seal of ages, I am preparing 

 to approach the torrid zone, where I hope to shew to Italy that 

 I am not entirely unworthy of belonging to her. 



Art. XVI. Proceedings of the Royal Society, 



The meetings of the Royal Society were resumed after the 

 long vacation, on Thursday, November 9, at which meeting a 

 letter was read from M. Ampere, of Paris, to the President, 

 containing an account of some electro-magnetic experiments, 

 which our readers will find adverted to in a preceding article. 



On the same evening Sir Everard Home communicated some 

 observations on the influence of the black substance in the 

 skin of the negro, in preventing the scorching operation of the 

 sun's rays. As black surfaces become much warmer by ex- 

 posure to the sun's rays than those which are white or of paler 

 tints, the cause of the black colour in the negro has long ap- 

 peared problematical to the physiologist. In this paper, Sir 

 Everard shows, that by exposing the back of the hand and 

 other parts of the body, covered with thin white linen, to the 

 direct influence of the sun's rays, they became irritated and 

 inflamed ; small specks or freckles first appear, and these, on 

 continued exposure, are followed by a vesicular separation of 

 the cuticle ; the same happens when the bare surface is ex- 

 posed, which, in common language, becomes sunburnt ; when, 

 however, the part of the body thus exposed is covered with a 

 piece of black crape, though the temperature of such part, when 

 exposed to the bright sunshine, exceeds that produced upon 

 the bare skin, the scorching and blistering influence of the rays 

 is entirely prevented ; hence it appears, that the deleterious 



